Polyphosphazenes and their synthesis
US5104947A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 7, 1989 |
| Grant date | Apr 14, 1992 |
| Priority date | — |
| Expiry date | Aug 7, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G79/025
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Described are polyphosphazenes which may be represented by the general formula ##STR1## in which R is a hydroxy-substituted or protected hydroxy-substituted saturated aliphatic group, R' is a hydrocarbyl group, R" is a residue of an alpha amino acid, n is from about 50 to about 25,000, and x is a number averaging from 0.05 to 1.00 per repeating unit and y is a number averaging from 0.95 to 0.00 per repeating unit so that per repeating unit the sum of x and y is 1. Removal of the protecting group in the R moiety renders the polymers water soluble. The polymers have a controllable set of properties including degree of hydrolytic stability, permeability, hydrophilicity, and bioacceptability. They may be used in the production of hydrogels for drug release systems, plasma extenders, and biomedical implants.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.